title: Determination of alpha-tocopherol, free cholesterol, esterified cholesterols and triacylglycerols in human lipoproteins by high-performance liquid chromatography.
abstract: The determination of alpha-tocopherol, free cholesterol, esterified cholesterols and triacylglycerols in human plasma and in fractions containing individual lipoproteins was achieved by reversed-phase high-performance liquid chromatography (HPLC). The lipoprotein fractions, such as chylomicron, VLDL, LDL, HDL2 and HDL3, were collected by ultracentrifugation of human plasma. The chromatographic separation was accomplished with a column packed with Hitachi Gel 3057, which is a spherical octadecylsilica of particle size 3 microns. The mobile phase was acetonitrile-2-propanol (75:25, v/v), and the eluate was monitored with ultraviolet absorption and fluorescence detectors connected in series. Qualitative analysis of the main chromatographic peaks collected during the HPLC of a plasma sample was done with the use of field-desorption mass spectrometry. The determination analysis of alpha-tocopherol, free cholesterol and esterified cholesterols was effected with a single chromatographic run with n-hexane extracts of plasma or lipoprotein fraction. The separation and determination of these fat-soluble components required as little as 5 microliters of plasma or lipoprotein fraction.
authors.affiliation: Analytical Instrument Division, Yokogawa Electric Corporation, Tokyo, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Seta
authors.forename: H
authors.initials: H
authors.lastname: Nakamura
authors.forename: T
authors.initials: T
authors.lastname: Okuyama
mesh_terms: D002784:Cholesterol / Q000032:analysis* / Q000097:blood; D002788:Cholesterol Esters / Q000032:analysis* / Q000097:blood; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D006801:Humans; D008074:Lipoproteins / Q000032:analysis* / Q000097:blood; D014280:Triglycerides / Q000032:analysis* / Q000097:blood; D014810:Vitamin E / Q000032:analysis* / Q000097:blood
chemical_list: D002788:Cholesterol Esters; D008074:Lipoproteins; D014280:Triglycerides; D014810:Vitamin E; D002784:Cholesterol